Rear IRS adjustment...

[lowboy]

In the original Sterling assembly instructions (for aesthetics) they recommended you readjust the rear springplates a couple of notches on an IRS chassis so as to lower the rear wheel well. I confess, I never did that. So yes, it does look a little high on the leg in the rear, and my tire size doesn't help it look any better. (All 4 tires the same size)
But I was wondering, how many people out there made that adjustment? And if you did, does it affect the handling?

If you went the big & little tire route, does that affect the handling?

How many just don't care?*asleep*

 

[Brastic]

My Sterling was lowered a little to far. As in, I am on the bump stops. Who needs a rear sway bar when you have no suspension travel. Even on the bump stops, I still have a large gap around my rear wheels. I am running 225/60/14 on the rear. I am looking for some good used 15x9 rims to put on larger rear tires. I will also cut the bump stops and raise the rear one notch.

It would not affect handling too much on the street. It is not too ugly of a job to lower the rear end and you should think about taking a day to do it.

 

[Unofun]

Adjustable spring plates are worth it!

If your going to adjust your suspension you might as well go ahead and put adjustable spring plates on it! It solves all kinds of problems such as bar sag on one side, past mis-adjustmests and so on. and once done rearend hieght takes less than 5 minutes to adjust.
100+ bucks well spent! *thumbs up*

As for the Bigg'n little tires, I am a real fan *thumbs up* It is a real easy way to get those freeway flyer gears your looking for, Improves visability out the front windshield and gives the front end the Apperance of a lowered look, and just improves the overall look without changing the speedo accuracy.

It also has the added effect of not needing a spare if you have a flat on the rear, as the bigger, stronger sidewalls will usually support the car to drive modestly to get it repaired such as when your out in the desert between Vegas and Baker!

 

[ydeardorff]

I remember reading about doing this adjustment when I had my 1961 bug. I also remember if not done right it could be very dangerous to the mechanic, as Ive heard. I never played with the spring plates. Ill have to look into that.

Using warrens red turbo rotary, what would the adjustments used on this suspension? both front and rear on his car look spot on, to what the avg sterling ride height should be set at.

 

[farfegnubbin]

As I wasn't the builder of that red car, I have no idea whether the spring plates were adjusted or not. *sigh* I like the way it looks, but I don't know if they reset the spring plates or whether they just got lucky with the slight additional weight of the water-cooled engine. Just don't know.

I know that, if anyone is going to attempt the adjustment, there are some good write-ups on TheSamba.com. I also like Greg's advice that, if you're going to take it all apart anyway, then go with adjustable plates which will let you dial in EXACTLY what you want.

 

[time907356]

I was thinking about lowering the Cimbria in the rear as well, but my experience is this: When I had my speedster, the body sat high in the rear, as does the Cimbria. I made the adjustment 3 times on the Speedster, trying to get the right look. In the end, I left it high, as the wheels rubbed on every corner and bump.
The Cim's wheels are much wider, and since the IRS has only one knuckle at the TA, the wheels are heavily undercambered. Aside from looking absolutely ridiculous from the rear, the handling has got to be crap (I haven't been on the road yet), and probably downright dangerous.
I actaully have the suspension wratchet-strapped down right now, but am thinking about the adjustment.
The 'clicks' on the standard suspension/spring plates are quite course; if you're 'just a little high', then one click will make it 'just a little low.'
I agree with the adjustable spring plates in the back. Continuous adjustment is the key. Sometimes, quite often in fact, I've seen dub's listing to one side, as well as their counterpart kit cars. Looks stupid - to have a 'supercar' look, leaning 1/2 degree left...All this to say, I'm on board.
I'm wondering though; do those silvery shocks have a spring in them too, or are they just dampeners - Anyone??

 

[Brastic]

I have the same problem with my Sterling. It is too high in the rear. My car is on the bump stops. The good news is that I have no reason for a sway bar, the bad news is that it rides like crap. I started talking around and I found one VW guy who solved the problem. He switched the trailing arms. This way you can lower the rear end and not have the crazy camber issue either. There is not a lot of work to be done, but you will have to grind off and weld the shot support. As for the car leaning, if the suspension is level then you will need to work on the body. There is not way around this. The last thing you want to do is to use the suspension to fix a body issue. This will leave to bad (possibly down right scary) driving.

 

[time907356]

In looking further at mine, the axles are angled too far down, causing the camber issue, but since the rear is too high, simply lowering the rear a bit is the win-win solution; reduces camber and brings the rear down.
The other issue is that the wheels are too far back in the wells. I think the rear was raised to avoid contact with the rear of the well. Can the spring plates be shortened to bring the wheels forward? That would be perfect, as only 1/2" of forward movement is needed.
Adjustable spring plates are cheap, ~$100/pair. Once I figure out how long my torsion bars are, I'll have a pair on order...

 

[letterman7]

All factory spring plates have slotted holes to allow for caster adjustment; it's possible that you could slide yours forwards to center the wheels a little more. IIRC, those slots are about an inch long. I imagine that aftermarket plates are the same way. There is a great article here Meyers Manx, Inc. on how to adjust the torsion rods. Remember, there are two sets of splines which, when combined, allow minute adjustments to be made - but you have to know what you're doing. Adjustments using the combined splines can be as small as 7/8 of a degree.

 

[time907356]

Rick,
A great read, and a reminder that the rear end is sufficiently adjustable without the expense of new adjustable spring plates. The writer changed his names for things a few times, which made it a bit challenging to follow (spring plates=swing plates=torsion arms...)
The logic I used on the Speedster was this: Why buy the adjusters if the rear end is configurable enough as is? The answer; I raised and lowered the Speedster 3 times looking for the right height! Call it indecision, but once is enough for this operation. It's definitely a 2 hr. affair, even after one becomes proficient.
The adjusters make this a 20 minute job after they are installed, if that. Plus, it adds the ability to cure the side to side listing if there is any.
I've had my suspension wratcheted down for a week, and just let it loose last night. The undercamber returned, though slightly. I'm sure I could use new bushings as well, so I'm still thinking the adjusters will be necessary.
Incidentally, I've been working on the windshield wiper for the past two days. I had to replace the welded output shaft that goes to the main wiper from the drive inside the car; it had rusted at the snap ring and broken off. cutting the head off of an 8 x 90mm shcs and welding it back in place of the shaft worked well. I had to hand-grind the sides of the screw to replace the flats that engage and drive the wiper blade. I realize this is fairly cryptic if you haven't done one before...

 

[letterman7]

I agree (about adjusting the spring plate angle). I did that with my Manx and swore I'd never do it again. Broke several strut spring compressors trying to collapse the plates, bent a farm jack (with chain welded to the foot) trying to re-set said plates onto their stops and generally created a mess. And learned a whole new cuss word vocabulary in the process...

 

[time907356]

I hope you didn't get hurt! I had a scissor jack fall over doing it...there's a lotta twist on those bars!

BTW - how does one determine how long his torsion shafts are in order to buy the correct adjustable spring plates, since they are ordered by rod length? I wouldn't have thought the torsions shaft length would make any difference!

 

[letterman7]

Long rod = IRS rear; short rod = swingaxle

According to the CIP1 site:

Note: All adjustable spring plates are made to use the short (21 3/4) torsion bars. This is a stock torsion bar for the 1960-68 beetle with the solid 4 bolt torsion cap. (with no hole in center). When changing over you well also need to use our torsion cap # ACC-C10-4055 to replace your old ones with the hole. On the later model IRS dog leg (trailing /swing arm ) the bolt pattern is slightly different - and therefor you will need to drill one extra hole for proper installation. Will provide approx. 1-1/2 to 2 inches of adjustability.

But then, CB Performance lists various years with options and their plates seem to be heavier duty... and pricier: CB Performance - Online Catalog A phone call to either tech department with your year chassis would certainly narrow it down.

 

[time907356]

If I only knew what year chasis it was...the title is for a re-cconstruction, with no reference. If Amore was only still in business...

 

[letterman7]

That's the easy part - post the VIN number, located on top of the tunnel. You can decode it from there using this chart: TheSamba.com :: Beetle VIN numbers

 

[time907356]

...Top of the tunnel by the rear beam, and shift linkage as I recall (?) My linkage cover is literally a piece of plywood bolted down. It has a number inked on it, so that might be the VIN itself! I'll check the tunnel for the stamping also.

 

[letterman7]

Yup, in front of the shifter link, about 4 inches or so. It should sit in a small indentation in the metal, visible as a gentle crease under your plywood!

 

[time907356]

118533017 = Jan/Feb 1968. It was written on top of the plywood! Now to the torsion bar length...

 

[time907356]

I got the reply from Pacific Customs, the cheapest priced adjustable spring plate provider:

Well 68 was the last year of swing axle and 69 was the first year of IRS. IRS never had short bars ( that don't stick through the torsion cover ). So that means over the time of that pan, someone has done some changes other than stock. Assuming it is IRS and short bars this is what you'll need:

I provided these specs:

It's IRS (one knuckle on the half axle, at the TA), and I the cover is solid. I'm not at the car, but will verify tonight.

Is this a "Swing Axle" car? Maybe I don't understand the swing designation.

 

[letterman7]

Actually, '68 was the changeover year with IRS coming in midway through the production run. An IRS rear has two very distinct knuckles, one at the backing plate on the wheel side and one on the transaxle side. The drive axle is only about an inch and an eighth thick. Swingaxles have only one "knuckle" at the transaxle side, covered with a large boot. Those drive axle tubes are about 2 1/2" thick and terminate inside the backing plate on the rear wheel. It's called swing axle because only one side of the axle pivots - the transaxle side.